Williamsoniaceae

Williamsoniaceae is a family within the Bennettitales, an extinct group of seed plants. Members of this family are believed to have been around two meters tall and with widely serrate leaves along a central stem. Reproductive organs of the Williamsoniaceae have varied widely in the fossil record but almost all have been found to be borne on stalks emerging from a ring of leaves.
File:Fossils_and_schematic_drawing_of_Pterophyllum_bavieri_from_the_Triassic_of_Iran.jpg|thumb|Fossils and schematic diagram of Pterophyllum bavieri from the Late Triassic of northern Iran, Shemshak Group, A and B: leaves attached to a branch C: complete leaf

Reproduction

This family is different from Cycadeoidaceae by having the presence of cones leaving the major axis and lateral branches associated with a long peduncle covered by bracts. Some of this family reproduce by sporangia and others only produce ovule or pollen sacs.